Method of attaching textile tapes of slide fastener elements to plastic sheets



April 6, 1954 J. ZOBEL 2,674,559 METHOD OF ATTACHING TEXTILE TAPES OF SLIDE FASTENER ELEMENTS TO PLASTIC SHEETS Filed May 4, 1949 ATTORNEY Patented Apr. 6, 1954 METHOD OF ATTAC HING TEXTILE TAPES OF SLIDE FASTENER ELEMENTS T-O PLAS- TIC SHEETS Joseph Zobel, Corpus Christi, Tex. Application May 4, 1949, Serial No. 91,302

3 Claims. 1

This invention broadly relates to the method of uniting by heat-sealing thermoplastic articles and textile fabrics, and especially deals with the attachment of textile supporting tapes for slide fastener elements with plastic sheets, the method of effecting such attachment, the device to facilitate that method and the finished product produced by said method and in such device.

Ever since slide fasteners and thermoplastic sheeting became widely used in commerce in recent years, innumerable unsuccessful attempts have been made to find a practical and effective way of attaching cloth fabric slide fastener tapes to thermoplastic sheeting by heat-sealing. Because of the many failures in attempting to produce satisfactory and secure juncture between textile and plastic by heat-sealing, it was found more simple and less troublesome to forego that method and resort to the ordinary way of stitchconnecting the two articles, such as has been used up to now for attaching a slide fastener to textile articles.

In View of the difficulties experienced by manufacturers in the application of slide fasteners to thermoplastic articles, there have been brought on th market textile supporting tapes for slide fastener elements wherein thermoplastic threads are woven into the tape material, but even that expedience has not proved to solve the problem of effecting a dependable and commercially acceptable juncture between such tapes and thermoplastic articles by heat-sealing. As a result the old sewing method has been resorted to even for attaching to plastic articles tapes bearing plastic matter in their textile structure.

The present invention contemplates overcoming and does successfully overcome the heretofore encountered dimculties of joining by heatsealing thermoplastic articles with textile fabrics, and especially as applied to cloth or fabric supporting tapes for slide fastener elements.

One of the objects of the present invention is the method whereby textile slide fastener tapes are effectively united by fusion with thermoplastic material, in such a way that the thermoplastic material is caused to penetrate the textile and securely imbeds itself therein.

Another object of this invention is the method of connecting by heat-sealing the textile fabric tapes of a slide fastener with thermoplastic sheet material, wherein such material is applied to and penetrates through both faces of the textile fabric of the tapes until fusion occurs.

Another, more specific object of this invention is the method of uniting by heat-sealing textile supporting tapes of a slide fastener with thermoplastic sheet material, and which method comprises sandwiching the textile tapes between the thermoplastic sheet and thermoplastic strips and subjecting the thus superimposed layers to pressure and heat until fusion occurs between the thermoplastic layers through the textile fabric of the tapes.

A still more specific object of this invention is the method of seal-uniting cloth fabric tapes with the future openable edges of a thermoplastic cover or envelope, and which method includes a succession of steps as follows: first, placing upon a support two relatively narrow, uniformly spaced strips of thermoplastic material; second, superimposing upon these strips the element-supporting tapes of a closed slide fastener so that the strips are equally spaced from the slide fastener elements; third, superimposing over the closed slide fastener structure, including its strips, a sheet of thermoplastic material constituting th future openable portions of the envelope; fourth, exerting pressure and heat against the strips and against those areas of the sheet which are opposite to said strips until fusion occurs between the sheet material and the material of the strips; and fifth, severing the sheet along one outer side of the closed slide fastener elements, whereby a flap is formed from the sheet along the edge of one of the openable envelope portions, and which flap serves as backing for the closed or partly closed fastener elements.

A still further object of this invention is the aforesaid method, which includes holding under longitudinal stretching tension said thermoplastic strips, holding under similar longitudinal stretching tension the closed slid fastener structure, and holding said sheet under tension, transversely to the length of the slide fastener and the strips, before and while pressure and heat are being appiied and until fusion between the material of the sheet and of the strips through the cloth fabric of the tapes takes place.

Another important object of the present invention is the provision of a device for practicing the above outlined method.

A still other object of this invention is th provision of a device constituting a die, composed of male and female members, and wherein at least one or both members are heatable, or where in heat may be supplied by electronic means, and wherein the female member is provided with centrally arranged means for the reception, guidance and holding that portion of a slide fastener structure, which includes the interlocked slide fastener elements, and wherein a pair of other means are provided for the reception of relatively narrow strips, said strips-receiving means being arranged symmetrically to and being uniformly spaced from said first-mentioned means, said male member having longitudinally extending bosses or projections aligned with the reception means for said strips, and a spare-out above the reception means for the interlocked fastener elements, said projections being adapted to exert pressure against the reception means for said strips.

A still further object of the present invention is the provision of an enveloping device produced by the above method and with the aid of the aforesaid device, and which envelope comprises a normally closed thermoplastic structure having openable portions, and which openable portions are equipped with a closeable slide fastener united by heat-sealing through its textile cloth tapes along the edge areas of these openable portions, and wherein these tapes are united at their interior surfaces with the exterior surfaces of these edge areas, and wherein the exterior surfaces of the tapes are provided with thermoplastic, preferably opaque strips equally spaced from the fastener elements, and wherein the marginal area of one of the openable portions of the envelope extends beyond the fastener elements in the form of a flap. which latter serves as a backing for the fastener elements.

The aforestated and additional objects and important advantages of the present invention will become more fully apparent from the ensuing specification, including the description of the accompanying drawings, which latter are designed to more or less diagrammatically convey the underlying thought of the present invention and are intended to serve for explanatory purposes only, and not in a restricting sense in respect to this invention, and in which drawings:

Fig. 1 illustrates a garment cover or envelope produced in accordance with the present invention;

Fig. 2 is a perspective view of a luggage envelope, also produced in accordance with the present invention;

Fig. 3 is a diagrammatical illustration in perspective view of a device for practicing the aforeindicated method;

Fig. 4 is an enlarged vertical cross sectional view through the device;

Fig. 5 is a cross section taken through the closeable areas of an envelope produced in accordance with the present invention; and

Fig. 6 is a diagrammatical illustration of representations of three articles to be joined in accordance with the present invention.

Thermoplastic covers and envelopes equipped with slide fastener closures, for covering garments, luggage and other articles do not present any novelty in the art, however, in their representation illustrated in Figs. 1 and 2 it will be noted that both thermoplastic envelopes l and II are equipped with slide fastener closures gen erally indicated at I2, which are entirely different in appearance alone from heretofore used similar slide fastener closures, even without taking into consideration their structural arrangement. In both devices these slide fasteners prominently differentiate over heretofore used slide fastener structures by two parallel plastic strips I3 which are immediately discernible. Each of the envelopes have openable ortions M which may be closed by means of slide fasteners 12.

As will be seen from Fig. 5, the slide fastener structure is joined with the edge areas of openable envelope portions M in that its textile fabric tapes l and I6 are connected with the thermoplastic sheet material by fusing the material of the sheet with the material of the two parallel strips 13 through the bodies of tapes l5 and I6, as indicated at l1.

The method employed to effect a commercially acceptable and dependable connection between textile fabrics and a thermoplastic sheet in accordance with the present invention necessitates the employment of thermoplastic material at both faces of the textile fabric to produce an interfusion of the two thermoplastic layers and the penetration of the thermoplastic material, while thus fused, through textile fabrics.

In diagrammati-cal Fig. 6 the typical co-relation between the articles to be joined is clearly indicated. Strips l3 are lowermost, slide fastener tapes l5 and 16 form the middle layer, and a sheet of thermoplastic material l4, constituting the future openable portions of the envelope, is disposed topmost.

A typical device facilitating the production of openable envelopes in accordance with the present method is shown in Figs. 3 and 4 and comprises a die structure composed of a male member l8 and a female member or matrix I9. Either one or both members are adapted to be heatable by suitable means, such as electric resistance elements indicated at 20, or suitable electronic means, not shown. Female member [9 is provided with a center longitudinal recess or groove 2| which is sufficiently deep to accommodate the interlocked fastener elements 22 of a slide fastener in such a way that either successive portions of these elements, or the entire length of interlocked elements are guided in the groove and are held therein against displacement, although they are capable of a slight bodily movement lengthwise and transversely in respect to the groove. Arranged symmetrically and-in parallel relation to groove 2|, but being spaced therefrom by ridges 23, are side grooves 24 which are shown to be shallower than center groove 2|. These side grooves are adapted for the accommodation of the relatively narrow plastic strips 13.

It is preferred that groove 2! as well as side grooves 24 are of a length corresponding to the length of the slide fastener to be employed, but when a fastener structure is very long, the grooves may be made shorter than the slide fastener, in which case the attachment of the slide fastener to the envelope body may take place in successive stages.

The male member is provided at its surface facing the female member with two spaced, parallel, longitudinal bosses or depending extensions 25 which are aligned and are preferably centered in respect to side grooves 24 of the female member. Between extensions 25 there is provided a spare-out 26 which is of a sufficient dimension to freely accommodate that portion of sheet 14 which overlies the interlocked fastener elements 22 and those portions of fastener tapes [5 and i6 which extend from the fastener elements over ridges 23 into side grooves 24, when the male and female members are brought into adjacency by pressure.

The method It is preferred that strips [3 are kept under slight longitudinal tension, as indicated by arrows I and II in Fig. 6, to cause them to adhere to the bottom of grooves 24 and to prevent them from forming wrinkles at any part of their body. In order to facilitate tensioning, strips l3 are made sufliciently long so that their ends can be gripped. Similarly it is preferred that the entire slide fastener structure is kept under longitudinal tension, as indicated by arrows III and IV, by way of its tapes which extend slightly beyond the structure for gripping and stretching them, whereas plastic sheet I4 is preferably held under tension transversely to the length of fastener 12, as indicated by arrows V and VI in Fig. 6. While the different items are thus held under tension, the hot male and female members of the die are moved against one another, whereby extensions are caused to compress the three layers within side grooves 24. Both pressure and heat are continued until complete fusion occurs between the material of sheet l4 and the material of strips 13 and the fused plastic penetrates through the textile fabric of the tapes, whereby a perfect and lasting union between all three superimposed layers along the areas substantially defined by grooves 24 is effected.

Now sheet M is severed along line 21 by a suitable cutting instrument, such as indicated at 28 in Fig. 4. The cut is preferably made to one side of the interlocked fastener elements 22, whereby a backing flap 29 is formed along the edge area of one of the closing portions 14 of the envelope. This flap is adapted to normally extend over and preferably somewhat beyond the width of fastener elements 22 when they are either in interlocked position, as shown in Fig. 4, or when partly separated, as in Fig. 5, and is intended to serve as a backing for the slide fastener element in envelope structures, such as or similar to those shown in Figs. 1 and 2.

By consulting Figs. 3 to 6 it will be seen that the envelope material is of a somewhat lesser thickness than that of strips I3. This is done to more readily facilitate fusion of the two plastic elements, and to compensate for the loss of plastic material from sheet 14' as it penetrates tapes I 5 and 16. In other words it is intended that from the greater thickness of tape l3 a suflicient portion of fusing plastic material enters the textile tape to prevent an excessive loss of plastic from sheet 14'.

Conclusion In the foregoing a specific method is described for equipping envelopes made of thermoplastic sheet material with the textile tapes of slide fasteners, wherein thermoplastic material is caused to penetrate the textile tapes. Obviously the above specific method does not preclude the employment of a textile tape for slide fastener elements or textile fabrics wherein thermoplastic thread is interwoven with the textile material, since the ultimate effect of interfusion of plastic between upper and lower plastic layers will remain the same. Similarly a specific device for practicing the above outlined method is illustrated in the drawings and described in the specification. It is evident, however, that both the outlined method as well as the device for practicing that method may have to be changed, depending upon future specific requirements. However, such changes are deemed to reside within the broad scope of the present invention as defined in the annexed claims.

I claim:

1. The method of attaching by heat-sealing cloth tapes, such as the supporting tapes of a slide fastener, to a thermoplastic sheet which comprises arranging the tapes in parallelism and in close adjacency to each other, placing the tapes between parallelly spaced strips of thermoplastic material and said sheet, holding the tapes, the strips and the sheet under tension and fusing the material of the sheet and of the strips through said tapes by subjecting those portions of the sheet which are disposed opposite said strips and the strips and the tapes between the sheet and the strips to pressure and heat and severing the sheet along a straight line centrally between said tapes.

2. The method of attaching by heat-sealing the supporting cloth tapes of a slide fastener to a sheet of thermoplastic material, which comprises closing the slide fastener and placing the tapes of the closed fastener over two parallelly spaced strips of thermoplastic material, holding these strips and the fastener tapes under tension and against displacement, placing a sheet of thermoplastic material over the entire closed fastener structure, including its tapes and its fastener elements at the face opposite said strips, holding the sheet under tension in a direction transverse- 1y to the length of the slide fastener and fusing the sheet material with the strip material through the cloth tapes by subjecting the strips, the fastener tapes and those areas of the sheet opposite said strips to pressure and heat.

3. The process of securing by heat-sealing to a thermoplastic sheet a slide fastener structure, the fastener elements of which are supported by cloth fabric tapes, which process comprises securing in place against movement two parallelly spaced, relatively narrow thermoplastic strips corresponding in length to that of the slide fastener, closing the fastener, superimposing upon the strips the tapes of the closed fastener so that a narrow margin is left between the interior edges of the strips and the interlocked fastener elements and keeping the tapes in position by tension, placing a thermoplastic sheet to which the fastener structure is to be secured over the fastener structure and holding the sheet under tension transversely to the length of the structure, and fusing the material of the sheet and of the strips through said tapes by subjecting the strips, the tape areas adjacent the strips and the areas of the sheet adjacent the tapes to pressure and heat and forming a backing flap for the fastener elements, while the latter are either closed or partly separated, by severing the sheet along one edge of the interlocked fastener elements.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,595,107 Lyng et al Aug. 10, 1926 2,130,930 Sipe Sept. 20, 1938 2,203,822 Hyman June 11, 1940 2,211,143 Mahoney Aug. 13, 1940 2,238,391 Carman June 30, 1942 2,423,237 Haslacher July 1, 1947 2,425,388 Oestricher Aug. 12, 1947 2,448,940 Whittemore Sept. 7, 1948 2,475,277 Budnik July 5, 1949 2,478,132 Schade Aug. 2, 1949 2,482,981 Kamrass Sept. 27,1949 2,490,946 Cloud Dec. 13, 1949 

1. THE METHOD OF ATTACHING BY HEAT-SEALING CLOTH TAPES, SUCH AS THE SUPPORTING TAPES OF A SLIDE FASTENER, TO A THERMOPLASTIC SHEET WHICH COMPRISES ARRANGING THE TAPES IN PARALLELISM AND IN CLOSE ADJACENCY TO EACH OTHER, PLACING THE TAPES BETWEEN PARALLELLY SPACED STRIPS OF THERMOPLASTIC MATERIAL AND SAID SHEET, HOLDING THE TAPES, THE STRIPS AND THE SHEET UNDER TENSION AND FUSING THE MATERIALS OF THE SHEET AND OF THE STRIPS THROUGH SAID TAPES BY SUBJECTING THOSE PORTION OF THE 